Gigabytes to Megabytes
Convert gigabytes to megabytes instantly — one gigabyte is 1000 megabytes.
| Gigabytes | Megabytes |
|---|---|
| 1 GB | 1000 MB |
| 2 GB | 2000 MB |
| 3 GB | 3000 MB |
| 5 GB | 5000 MB |
| 10 GB | 10000 MB |
| 25 GB | 25000 MB |
| 50 GB | 50000 MB |
| 100 GB | 100000 MB |
How to use
- Enter a value in the Gigabytes field.
- The Megabytes figure appears immediately — no button to press.
- Typing in the Megabytes field converts back to Gigabytes the same way.
- Use the reference table for the values that come up most often.
Gigabytes to Megabytes formula
The factor from gigabytes to megabytes is 1000.
MB = GB × 1000
Put another way, one gigabyte is exactly 1,000 megabytes.
Why this factor: the gigabyte and the megabyte are both defined against the byte, so dividing one definition by the other gives 1000 directly. Both definitions are set out in full below.
To go the other way, divide by 1000 — or use the Megabytes to Gigabytes converter, which is the same calculation reversed.
Worked example
Given 4 GB, multiplying by 1000 yields 4000 MB.
4 GB × 1000 = 4000 MB
The converter above does this for any value you type, in either direction.
What is a gigabyte?
A gigabyte is one billion bytes — the everyday unit of storage and memory capacity.
Definition: Exactly 1,000,000,000 bytes under SI prefixes. The binary gibibyte (GiB) is 1,073,741,824 bytes.
Where it is used: Phone and laptop storage, RAM capacity, video file sizes, and cloud storage plans.
What is a megabyte?
A megabyte is one million bytes, the familiar unit for photos, songs and app sizes.
Definition: Exactly 1,000,000 bytes under SI prefixes. The binary mebibyte (MiB) is 1,048,576 bytes.
Where it is used: Photo and audio file sizes, app downloads, and mobile data allowances.
Gigabytes vs Megabytes
The gigabyte and the megabyte belong to the same family of units, so converting between them is usually a matter of shifting a decimal point or applying a small whole-number factor.
Frequently asked questions
How many megabytes are in a gigabyte?
One gigabyte equals 1000 megabytes.
What is the formula to convert gigabytes to megabytes?
Multiply the number of gigabytes by 1000. To reverse it, divide by 1000 instead.
How do I convert megabytes back to gigabytes?
Divide by 1000, which is the same as multiplying by 0.001.
How many megabytes are in 10 gigabytes?
10 GB works out to 10000 MB.
How is the gigabyte defined?
Exactly 1,000,000,000 bytes under SI prefixes. The binary gibibyte (GiB) is 1,073,741,824 bytes.